function clear_mem () {
  var form = document.forms.booking_details;
  if (form && form.mem_num) {
    form.mem_num.value = '';
    
    var new_mem_discount = document.getElementById ('discount_new');
    if (new_mem_discount) {
      new_mem_discount.disabled = true;
    }
    
    var new_mem_discount_year = form.YearBeganTeaching;
    if (new_mem_discount_year) {
      new_mem_discount_year.disabled = true;
    }
  }
}

function set_mem () {
  var form = document.forms.booking_details;
  if (form && form.membership) {
    form.membership[1].checked = true;
    
    var new_mem_discount = document.getElementById ('discount_new');
    if (new_mem_discount) {
      new_mem_discount.disabled = false;
    }
    
    var new_mem_discount_year = form.YearBeganTeaching;
    if (new_mem_discount_year) {
      new_mem_discount_year.disabled = false;
    }
    
  }
}

function clear_code () {
  var form = document.forms.booking_pre;
  if (form && form.key) {
    form.key.value = '';
  }
}

function set_code () {
  var form = document.forms.booking_pre;
  if (form && form['do']) {
    form['do'][1].checked = true;
  }
}

function set_new_member_discount () {
  var form = document.forms.booking_details;
  if (form && form.YearBeganTeaching && form.YearBeganTeaching.value != '') {
    form.Discount[0].checked = true;
  }
}

function show_hide_send_to () {
  var form = document.forms.booking_details;
  var node = document.getElementById ('send_to');
  var node2 = document.getElementById ('credit_card_info');
  
  if ((!form) || (!node) || (!form.PaymentMethodID)) return;
  
  if (form.PaymentMethodID.value == '1' || form.PaymentMethodID.value == '4') {
    node.style.display = '';
    node2.style.display = 'none';
    
  } else if (form.PaymentMethodID.value == '2') {
    node.style.display = 'none';
    node2.style.display = '';
    
  } else  {
    node.style.display = 'none';
    node2.style.display = 'none';
  }
}

function show_hide_el(name, show) {
  var node;
  
  node = document.getElementById(name);
  if (node == null) return;
  
  if (show) {
    node.style.display = '';
  } else {
    node.style.display = 'none';
  }
}


function update_avail_fields (role) {
  var show;
  
  if (role == 3) {
    show = false;
  } else {
    show = true;
  }
  
  show_hide_el ('row_abn', show);
  show_hide_el ('row_empl_sector', show);
  show_hide_el ('row_teach_exp', show);
  show_hide_el ('row_empl_site', show);
  show_hide_el ('row_location', show);
  show_hide_el ('row_school_sasta_member', show);
  show_hide_el ('row_position', show);
  show_hide_el ('row_user_sasta_member', show);
  
  if (role == 3) {
    if (document.forms.booking_details.elements.membership) {
      document.forms.booking_details.elements.membership.value = 0;
      clear_mem();
    }
    
    update_price ();
    
    document.forms.booking_details.elements.PaymentMethodID.value = 2;
    show_hide_send_to();
  }
  
  document.forms.booking_details.elements.PaymentMethodID.disabled = (!show);
}